Agreement in the Scoring of Respiratory Events and Sleep Among International Sleep Centers

Study Objectives: the American Academy of Sleep Medicine (AASM) guidelines for polysomnography (PSG) scoring are increasingly being adopted worldwide, but the agreement among international centers in scoring respiratory events and sleep stages using these guidelines is unknown. We sought to determine the interrater agreement of PSG scoring among international sleep centers.Design: Prospective study of interrater agreement of PSG scoring.Setting: Nine center-members of the Sleep Apnea Genetics International Consortium (SAGIC).Measurements and Results: Fifteen previously recorded deidentified PSGs, in European Data Format, were scored by an experienced technologist at each site after they were imported into the locally used analysis software. Each 30-sec epoch was manually scored for sleep stage, arousals, apneas, and hypopneas using the AASM recommended criteria. the computer-derived oxygen desaturation index (ODI) was also recorded. the primary outcome for analysis was the intraclass correlation coefficient (ICC) of the apnea-hypopnea index (AHI). the ICCs of the respiratory variables were: AHI = 0.95 (95% confidence interval: 0.91-0.98), total apneas = 0.77 (0.56-0.87), total hypopneas = 0.80 (0.66-0.91), and ODI = 0.97 (0.93-0.99). the kappa statistics for sleep stages were: wake = 0.78 (0.77-0.79), nonrapid eye movement = 0.77 (0.76-0.78), N1 = 0.31 (0.30-0.32), N2 = 0.60 (0.59-0.61), N3 = 0.67 (0.65-0.69), and rapid eye movement = 0.78 (0.77-0.79). the ICC of the arousal index was 0.68 (0.50-0.85).Conclusion: There is strong agreement in the scoring of respiratory events among the SAGIC centers. There is also substantial epoch-by-epoch agreement in scoring sleep variables. Our results suggest that centralized scoring of PSGs may not be necessary in future research collaboration among international sites where experienced, well-trained scorers are involved.NHLBITzagournis Medical Research Endowment Funds of the Ohio State UniversityOhio State Univ, Wexner Med Ctr, Div Pulm Allergy Crit Care & Sleep Med, Columbus, OH 43210 USAChang Gung Mem Hosp, Div Pulm Crit Care & Sleep Med, Tao Yuan, TaiwanRoyal N Shore Hosp, Dept Resp Med, Ctr Sleep Hlth & Res, Sydney, NSW, AustraliaUniv Sydney, Sydney, NSW 2006, AustraliaUniv Penn, Perelman Sch Med, Div Sleep Med, Ctr Sleep & Circadian Neurobiol, Philadelphia, PA 19104 USALandspitali Univ Hosp, Dept Resp Med & Sleep, Reykjavik, IcelandSir Charles Gairdner Hosp, West Australian Sleep Disorders Res Inst, Nedlands, WA 6009, AustraliaCharite, Ctr Sleep Med, Berlin, GermanyUniv Grenoble 1, INSERM, U1042, Lab Hypoxia & Pathophysiol HP2, Grenoble, FranceUniversidade Federal de São Paulo, Dept Psicobiol, Disciplina Med & Biol Sono, São Paulo, BrazilOhio State Univ, Ctr Biostat, Columbus, OH 43210 USAUniversidade Federal de São Paulo, Dept Psicobiol, Disciplina Med & Biol Sono, São Paulo, BrazilNHLBI: P01 HL094307NHLBI: HL093463Web of Scienc